The other day at work I had about 1000 rounds to burn. The first 10, 30 round magazines I shot just using rapid trigger pull. My barrel turned extremely blue/purplish, and was really hot. I grabbed another weapon, shot about another 9 magazines on burst, changed weapons and finished up the last of the magazines on a mix of burst and semi. I know it didn't hurt to change weapons but just for future reference how many rounds could I throw down range before it becomes hazardous to the barrel? I know when people get issued .50 cals, 240s and the 249s that you also get issued about another 2-4 barrels to switch out.

I can't really say about what's acceptable with 5.56/.223. I'd think that there would be a throat erosion gauge that would measure that readily and that there would be acceptable and unacceptable measurements. I suppose you could a barrel hot enough to warp as well.

Full auto fire would eat a throat up pretty quick. If you shot long enough and fast enough to discolor the barrel on the outside......think what the inside must look like!

I know that 7.62/308 for match standards is around 4-5000 rounds or so. That's for a paper puncher shot in 15-30 round single fire strings. Kinda depends on when accuracy deterioates.

I didn't even think that about what the inside of the barrel would look like if the outside looked like that. I have no clue about the barrel, somebody says "hey this is yours, don't lose it" and I take it. My buddy had his barrel so hot that he couldn't see through his scope while we were over seas.

Barrel so hot you cant see through the scope isnt hard on a summer day. People do it by accident with bolt guns. It's called mirage.

You may not have damaged it but to me if you are just shooting at the range for fun then getting the barrel that hot is stupid. What did you accomplish? Were you doing it to see what kind of 30 round FA groups you could hold? Were you just dumping ammo into a berm for the sake of wasting money? I mean its your gun and you are free to do with it what you want within the law but it's not what I would do.

Sounds to me like you just put un-neccessary stress and shortened the life of your barrel for nothing. If the barrel was so hot you couldn't touch it chances are the metal was softer than usual which means the barrel would have worn more with each bullet than is normal. Extremely minimally, and maybe not even noticeably depending on this gun's use (guessing it's not exactly a target gun).

Barrel life's based on how accurate the rifle barrel is when it's new.

If it starts out at no worse than 1/4 MOA, it'll last about 3000 rounds burning 1 grain of powder for each square millimeter of the bore's cross sectional area. Example, .308 Win. with 45 grains of powder, 45 square millimeters of bore cross sectional area. Or the 22 PPC; 22 grains of powder. The 6mm PPC; 28 grains of powder. These quarter-inchers all last about 3000 rounds for tack-driving accuracy. Best test of barrel life for the .308 Win. is that Sierra Bullets replaces their accuracy test barrels about every 3000 rounds. That's when they stop shooting 1/4 MOA at 200 yards with their best match bullets and test groups have started up into the 3/8 MOA range.

Barrels starting out at 1/2 to 3/4 MOA will get about twice as much barrel life. And barresl starting out at 1 to 1-/4 MOA may get four times as much. Typical are 30 caliber service rifles that last about 9,000 to 10,000 rounds for the accuracy their specs state.

Double the powder charge for a given bore diameter and barrel life drops by 75%. Huge 30 caliber magnums burning 90 grains of powder get 700 to 800 rounds of barrel life if they start out at 1/4 MOA.

Colt did tests on the M4 and M4A1 on full auto mag dumps without stopping to cool.

The M4 made it to around 540 rounds before the barrel drooped and burst.
The M4A1 made it to 910 or so before the rifle was on fire and unable to be used.

If you don't know the difference in the barrels google it. As for barrel life, Filthy 14 was a standard CL barrel that was getting 4-5MOA at 100yrds with 34,000 rounds through the barrel at rates of 1,300 every 3 days(this is considered a heavy firing schedule).

Its also woth noting that if you abuse a barrel by firing 10 or so mags without a break(this us abusive because no proper trainig can come from it) the throat will be gone by around 6,000-7,000 rounds.

Would I ever do that to my own weapon? No. Not unless it was called for. I work in a group of about 30 guys, give or take a few. We are required to go to the range every so often for work but we go more then we have to because we get out of work to go shoot and have some fun. The way it works in the army is that its super hard to turn in unused ammunition, so much to the point that the guys who give it to use tell us don't give it back unless its shells. They gave us 10,000 rounds one day for 30 guys to shoot. So the last 8 guys who were still at the range were left to dispose of it before the sun went down. When were home we play around, getting our weapons fixed is as easy as filling out some paper work and taking it to the armorer.

Our platoon had range detail, for a live fire, for a Scout platoon.
Scouts didn't show. We had one 1911a1, one grease gun, one M60, one H2, and one 90mm reciless rifle. One case .45, one pallet of 7.62, two cases of .50 and ? rounds of the 90mm. No one in charge but us. Had asbestos gloves to switch barrels. Took all day to shoot it up. Probably the best day at a range.

I subscribe to PatientWolf's theory. I will shoot quite a few rounds at the range on occasion but usually no more than 20 or so per rifle or handgun. Then other times only a few as in checking to make sure I am sighted in for hunting etc. To fire so much that the barrel turns blue or purple is purposely ruining your gun .

Well i suppose you could shoot a very high power round through a rifle barrel. It would have to be a relatively thin barrel like a .22 barrel and you would have to shoot it as close to perpendicular as possible. Just be careful because if it doesn't go all the way through it might bounce back.

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